Diamond-holder.



E C(STRONG. DIAMOND HOLDER.

APPLICATION FILED 00T.6, 1911.

Patented July 23, 1912.

FIG..2

FIG. 1

To all whom it may 2 STATES ATENT oFFrC ELI CHARLES STRONG, OF SHEFFIELD,

ENGLAND.

DIAMOND-HOLDER.

Specification of Letters Patent. P tented July 23, 1912.

Applicationfiled October 6, "-1911.

Serial No. 653,282.

concern:

Be it known that I, ELI CHARLES STRONG, a subject of the King of England, residing in Shefiield, in the county d certain new and useful land, have invente Improvements in poses,

of York, Eng- Diamond Holders, of

specification.

means in its setting it will still will not be lost, broken or require to be remounted. WVhen the diamonds are mounted rigidly in the holder by r a perforated screwed cap or has heretofore been the prachas to be exercisedv in using brazing, by otherwise, as t1se,'great care the tool as any sudden stress is liable to fracture the diamond or tear it from its setting. Even with is very, apt to become dition the liability to loss greatly, increased.

vided with screw perforated cap invention however idly mounted in the angles or points pro ture. in a cap which mond andthe seating for its base,

and seating being careful use the diamond loose and in that con-- or fracture is According to the present the diamond is not righolder but one of its ects through an aperincloses both the diathe cap pressed toward one another by a suitable spring. Thus the diamond is self-adjusting in its seating. The

effect of abnormal stresses and sudden blows is minimized and the diamond is not liable to become loose and as a consequence the tool has a greatlyprolong'ed life and can beused for much rougher work than has hitherto been the case.

,Further advantages the ease with which a and the practicability of using in'the holder of this invention are diamond. may be fixed a comparatively soft metal seating for the diamond without the disadvantages inherent therein when a rigid setting is employed.

In the accompanying. drawings -F igure 1 is a sectional elevation of a-diamond.h older according to this invention and Fig. 2 is a similar view of a modification.

Like letters indicate like parts throughout the drawings.

With reference of the diamond h first to Fig. 1 the stem A older is provided with a central longitudinal cavity or hole B at its free end. This en d of the stem is also prothreads to enable atapped C, to be screwed thereon.

for so that if .This cap G itself is 'of known construction, having previously been employed for the rigid setting of diamonds, the aperture in its apex being tapered to enable the diamondpartially to project therethrough.

helical spring D is situated within the cavcap C and movable member E in order that such screwing or unscrewing of the cap may not cause the diamond to turn in relation to either and *thus to cause damage. Such means may comprise a pin 0 on the interior of theoap engaging a suitable-longitudinal slot in the movable member E.

The effective strength of the spring D be"- ving sufli'cient to hold the diamond to its work without movement under normal conditions it will be appreciated that if the diamond experience any abnormal stress or sudden blow the spring will materially lessen its effect on'the diamond .and thus prevent fracture. Moreover even though the diamond be temporarily loosened in its setting thereby it will afterwards immediately be firmly held again and thus the abnormal stress or sudden blow will, notconduce to future fracture or loss of the diamond as would be the case if the setting were a rigid openingbeing provided for the insertion of the spring, diamond and seating of the latter.

' ity B and supports a movable member E ing a seating upon theend of the movable v It. is preferred to provide a means for preventing relative rotation of the 'In the modificatlon. illustrated in Fig. 2-

the cap G is not tapped but is arranged to fit loosely the free end of the stem A. The seatingfor' thediamond-is formed at the free end of the stem and the spring D is connected at one end to the cap Oand at the other to the stem A. The effective force exerted by the spring may be varied by con necting it to the stem by means of a nut G engaging a screwed part thereof. It-is pre ferred to provide means for preventing relative rotation of the capand stem such as by the pin C projectingfrom the interior of the cap and engaging a longitudinal slot in the stem. The same pin C extending to the exterior of the cap may be employed for the attachment of the spring D thereto. In this case it will be necessary for the connection between the nut G and spring D to be such as to allow these parts to turn in relation to each other. By using a spring coiled in the opposite sense to the screw threads on the stem A and in the nut G and providing a projection or projections G on the latter engaging the coils of the spring it Wlll be appreciated that as the nut is turned to increase the tension of the spring it will also shorten the effective length thereof and thus still more increase the tension. The projections G on the nut will also serve as means to enable the latter to be turned, although other means to connect the spring to the nut G so as to allow of relative rotation between them may be employed if desired, or the spring may be so connected to the cap C.

It is preferred to make that part of the stem A and movable member E which forms the seating for the diamond of some com paratively soft material such as copper in order. to enablethe diamond easily to ob tain a firm seating thereon, and, especially in the case of the modification illustrated in Fig. 2, in order to lessen the force of any blows on the diamond.

Other modifications may be made in the construction of the holder without departing from this invention as for example in the employment of difierent means for adjaisting the effective strength of the spring, or in the employment of difi'erent forms and arrangements of spring.

What I claim and desire to ters Patent is 7 1. In a diamond holder the combination of a stem, a perforated cap partially to inclose the diamond, a seating for the diamond, a spring pressing the cap and. seating toward one another and means forvarying the force exerted by the spring.

2. In a diamond holder the combination of astem having a cavity atone end, a spring within the cavity, a movable member partially within the cavity supported by said spring and having a seating. for the diamond, a perforated cap inclosing the movable member, mutually engaging screw threads on the cap and stem and means for preventing relative rotation of the cap and secure by 'Let- 'movable member.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ELI CHARLES STRONG.

Witnesses:

ARTHUR M. GREENWOOD, CHAs. N. DANIELS. 

